Given the following equation:

You can follow these steps in order to solve for "a":
1. According to the Distributive property, you know that:

Then you must apply the Distributive property by multiplying the terms inside the parentheses by "n":

2. Apply the Subtraction property of equality by subtracting "n" from both sides of the equation:

3. Apply the Division property of equality by dividing both sides of the equation by "n":

The answer is:
